At a local dive club meeting, the representative from Cochran Dive computers stated that one is under development for the military, and will be available to the public shortly after that.

But if you think about it, the price might be a bit out of reach for most sport divers. Currently hoseless computers start in the $700-800's. So if you add what is necessary for a HUD, that mask may be be even more.

If you think about it, batteries for most dive computers are not that large...something along the line of a watch or camera battery and weigh about the same as a medium size coin. So placing the battery somewhere around the mask is not that difficult.

I've never seen computer's batteries, but it's not a good idea of putting them IN the mask... What happen if the mask gets full of ocean water? The batteries whould have to be isolated or they will leak...

The battery for your dive computer is about the size of the button on your shirt, and not that much heavier. And simce most of these are sealed already, leakage of the chemicals is minimal.

The compartment will be appropriately sealed with an O-ring. And placement would be on the outside of your mask, say on the outer "rim". So even if you were to flood your mask (by accident or design), it would be unlikely that any battery contents would get into your eyes.